The USB Implementers Forum (USB-IF), the industry consortium behind the development of the Universal Serial Bus (USB) specification, announced this week it has finalized the technical specifications for USB4, the next generation of the spec.

One of the most important aspects of USB4 (they have dispensed with the space between the acronym and the version number with this release) is that it merges USB with Thunderbolt 3, an Intel-designed interface that hasn’t really caught on outside of laptops despite its potential. For that reason, Intel gave the Thunderbolt spec to the USB consortium.

Unfortunately, Thunderbolt 3 is listed as an option for USB4 devices, so some will have it and some won’t. This will undoubtedly cause headaches, and hopefully all device makers will include Thunderbolt 3.